The effect of the number of inseminations/cycles on the fertility of inseminated mares with diluted, cooled and stored jackass semen was studied. The cycles were controlled by rectal palpation and teasing, and mares were inseminated every Tuesday, Thursday and Saturday (three times/week), from the detection of a 3.0 to 3.5cm follicle diameter in one of the ovaries until ovulation. The semen of five Pêga jackasses was diluted in skim milk-glucose or in egg yolk-glicine diluter and cooled at 5ºC for 12 hours, with the inseminate dose of 400 x 10(6) motile spermatozoa (at the moment of the final dilution, before cooling). The results of 195 cycles of 140 mares were grouped, in accordance with the number of artificial inseminations (AI)/cycle in: 1AI, 2AI and 3 or more AI. The conception rates for the first cycle were 50.0%, 62.1% and 41.0%, and after four cycles they were 47.7%, 55.6% and 42.9%, respectively for 1AI, 2AI and 3 or more AI (p>0.05). The number of AI/cycles, using cooled jackass semen, had no influence on fertility.
jackass; number of inseminations; cooling semen; conception rate
